Food and medicine:
(1) Preservative
Benzoic acid and sodium benzoate have the effects of sterilization and inhibition of bacterial growth, and are low toxic and tasteless, so they are widely used as preservatives. In slightly acidic medium, only 0.1% concentration of benzoic acid can inhibit bacterial growth. Changing the pH value has a great impact on the bactericidal and bacteriostatic effects of benzoate. Its effect is significantly reduced in the reducing medium, and the effect is the best when the pH value is 2.5 ~ 4.5 .
In the food industry, benzoic acid and sodium benzoate can be used as preservatives for soy sauce, pickles, cider, fruit juice, feed, etc. Benzoic acid and sodium benzoate are also used as preservatives in drugs, cosmetics, toothpaste, perfume powder and tobacco leaves. Sodium benzoate has greater solubility in water and is usually used more, but its pH value is higher and its bactericidal and bacteriostatic ability is much weaker than that of benzoic acid .
(2) Drugs
Benzoic acid, sodium benzoate and benzyl benzoate can be used to manufacture various drugs to treat arthritis, abscess, bronchitis and skin diseases respectively. They can also be used as local anesthetics . Benzoic acid can be used to make benzoic acid salicylic acid ointment. Benzoic acid salicylic acid ointment is a medicament made of benzoic acid and salicylic acid as main raw materials and added lanolin and yellow Vaseline. Among them, the combination of benzoic acid and salicylic acid can treat adult skin fungal diseases and superficial fungal infections, such as tinea corporis, tinea manus and tinea pedis.
(3) Deodorant
benzoic acid can be used as a flavoring agent for fruit juice drinks. It can be used as a perfume to infuse incense. It can also be used in flavors such as chocolate, lemons, oranges, berries, nuts, preserves, etc. Tobacco flavors are also commonly used. Due to the low solubility of benzoic acid, it must be stirred well or dissolved in a small amount of hot water or ethanol. Benzoic acid is commonly used in cold beverage concentrates because it is easily volatilized with water vapor.
